I have a really hard time getting enough protein to build muscle. I'm trying to lose weight and I get about 70 grams of protein a day. Since protein is made up of amino acids, does supplementing with extra ones help your body make protein?

70g of protein a day? That's not even giving you 1g per 1lb bodyweight ~ you aren't consuming anywhere near enough protein. You should be aiming for a minimum of 1g per 1lb bodyweight, so until you increase your protein there really isn't any point adding in any additional BCAA's.

Can I ask how come you are having a hard time consuming enough protein? MF

I drink Vega Sport every morning for breakfast, I have a couple pieces of fruit and a handful of nuts mid-morning, usually a big salad for lunch with a can of peas on it. On training days I have another Vega Sport after my workout. For dinner I usually just have veggies and maybe some tofu. I am the only vegan in the family, so I don't eat the same dinner that they do. I get up at 4 am every day so I hate to mess around with cooking two dinners so I just eat what they do but I skip the meat. I am 57 and my thyroid died from Graves Disease about 30 years ago, so I just have a very hard time losing weight. I was keeping track of my food with the Lose It app and I am eating less than 1500 calories a day, working out three times a week and doing taekwondo but I still slowly put on weight. It is very disheartening. I tend to not eat a lot of beans and nuts because they are so high in calories. I did finally find a doctor who put me on a natural thyroid instead of synthetic thyroid so I have high hopes that my metabolism will pick up. Seriously, my resting heart rate is 54! I walk with my French Brittany for at least a half hour every day, too. I can't figure out why I can't lose weight!I am 5'7" and weigh 170. Ideal weight is 145-150.